The invention relates to the area of cell cycle progression. More particularly, the invention relates to proteins which regulate cell cycle progression.
Alterations in the regulation of cell cycle progression play an important role in diseases such as neoplasia and anemia. Manipulation of genes involved in regulating the cell cycle can be used to prevent or treat these diseases. Detections of mutations in cell-cycle regulatory genes can also be used to detect neoplastic cells and genetic predispositions to neoplasias. Thus, there is a need in the art for the identification of cell cycle regulator genes which can be used in methods of diagnosing, prognosing, and treating neoplasia and other diseases in humans and other mammals.
It is an object of the invention to provide reagents and methods for regulating mitosis or cell cycle progression in human cells and for treating disorders related to alterations in cell cycle progression. These and other objects of the invention are provided by one or more of the embodiments described below.
One embodiment of the invention is an isolated and purified human CIF130 protein comprising an amino acid sequence which is at least 85% identical to the amino acid sequence shown in SEQ ID NO:2. Percent identity is determined using a Smith-Waterman homology search algorithm using an affine gap search with a gap open penalty of 12 and a gap extension penalty of 1.
Another embodiment of the invention is an isolated polypeptide comprising at least 17 contiguous amino acids as shown in SEQ ID NO:2.
Yet another embodiment of the invention is a CIF130 fusion protein comprising a first protein segment and a second protein segment fused together by means of a peptide bond. The first protein segment consists of at least 17 contiguous amino acids of a human CIF130 protein as shown in SEQ ID NO:2.
Even another embodiment of the invention is a preparation of antibodies which specifically bind to a human CIF130 protein having an amino acid sequence as shown in SEQ ID NO:2.
Still another embodiment of the invention is a cDNA molecule which encodes a human CIF130 protein having an amino acid sequence which is at least 85% identical to SEQ ID NO:2. Percent identity is determined using a Smith-Waterman homology search algorithm using an affine gap search with a gap open penalty of 12 and a gap extension penalty of 1.
A further embodiment of the invention is a cDNA molecule which encodes at least 17 contiguous amino acids of SEQ ID NO:2.
Another embodiment of the invention is a cDNA molecule comprising at least 12 contiguous nucleotides of SEQ ID NO:1.
Still another embodiment of the invention is a cDNA molecule which is at least 85% identical to the nucleotide sequence shown in SEQ ID NO:1. Percent identity is determined using a Smith-Waterman homology search algorithm as implemented in a MPSRCH program using an affine gap search with a gap open penalty of 12 and a gap extension penalty of 1.
Even another embodiment of the invention is an isolated and purified subgenomic polynucleotide comprising a nucleotide sequence which hybridizes to SEQ ID NO:1 after washing with 0.2xc3x97SSC at 65xc2x0 C. The nucleotide sequence encodes a CIF130 protein having the amino acid sequence of SEQ ID NO:2.
Yet another embodiment of the invention is a construct comprising a promoter and a polynucleotide segment encoding at least 17 contiguous amino acids of a human CIF130 protein as shown in SEQ ID NO:2. The polynucleotide segment is located downstream from the promoter. Transcription of the polynucleotide segment initiates at the promoter.
Even another embodiment of the invention is a host cell comprising a construct which comprises a promoter and a polynucleotide segment encoding at least 17 contiguous amino acids of a human CIF130 protein having an amino acid sequence as shown in SEQ ID NO:2.
A further embodiment of the invention provides a homologously recombinant cell. The homologously recombinant cell incorporates a new transcription initiation unit. The new transcription initiation unit comprises an exogenous regulatory sequence, an exogenous exon, and a splice donor site. The transcription initiation unit is located upstream of a coding sequence of a CIF130 gene as shown in SEQ ID NO:1. The exogenous regulatory sequence directs transcription of the coding sequence of the CIF130 gene.
Another embodiment of the invention provides a method to aid in the diagnosis or prognosis of neoplasia in a human. Expression of a first CIF130 gene in a first tissue of a human suspected of being neoplastic is compared with expression of a second CIF130 gene in a second tissue of a human which is normal. The second CIF130 gene has the coding sequence shown in SEQ ID NO:1. Decreased expression of the first CIF130 relative to expression of the second CIF130 gene indicates neoplasia in the first tissue.
Another embodiment of the invention provides a method to aid in the diagnosis or prognosis of neoplasia in a human. A first human CIF130 gene, mRNA, or protein in a first tissue suspected of being neoplastic is compared with a second human CIF130 gene, mRNA, or protein in a second tissue which is normal. The second CIF130 gene has the coding sequence shown in SEQ ID NO:1. A difference between the first and second CIF130 genes, mRNAs, or proteins indicates neoplasia in the first tissue.
Yet another embodiment of the invention provides a method to aid in detecting a genetic predisposition to neoplasia in a human. A CIF130 gene, mRNA, or protein in a fetal tissue of a human is compared with a wild-type human CIF130 gene, mRNA, or protein. The wild-type CIF130 gene has the coding sequence shown in SEQ ID NO:1. A difference between the CIF130 gene, mRNA, or protein in the fetal tissue of the human and the wild-type human CIF130 gene, mRNA, or protein indicates a genetic predisposition to neoplasia in the human.
Still another embodiment of the invention provides a method of screening test compounds for the ability to interfere with the binding of a CIF130 protein to a CIF150/hTAFII150 protein. A test compound is contacted with at least a CIF150/hTAFII150-binding domain of a CIF130 protein as shown in SEQ ID NO:2 and at least a CIF130-binding domain of a CIF150/hTAFII150 protein as shown in SEQ ID NO:4. The CIF130-binding domain binds to the CIF150/hTAFII150-binding domain in the absence of the test compound. The amount of at least one of the CIF130- or CIF150/hTAFII150-binding domains which is bound or unbound in the presence of the test compound is determined. A test compound which decreases the amount of bound CIF130- or CIF150/hTAFII150-binding domain or which increases the amount unbound CIF130- and CIF150/hTAFII150-binding domains is a potential inducer of mitosis or cell cycle progression.
Another embodiment of the invention provides a method of screening test compounds for the ability to interfere with the binding of a CIF130 protein to a CIF150/hTAFII150 protein. A cell is contacted with a test compound. The cell comprises two fusion proteins. A first fusion protein comprises (1) a CIF150/hTAFII150-binding domain of a CIF130 protein as shown in SEQ ID NO:2 and (2) either a DNA binding domain or a transcriptional activating domain. A second fusion protein comprises a CIF130-binding domain of a CIF150/hTAFII150 protein as shown in SEQ ID NO:4. The CIF130-binding domain binds to the CIF150/hTAFII150-binding domain. If the first fusion protein comprises a DNA binding domain, then the second fusion protein comprises a transcriptional activating domain. If the first fusion protein comprises a transcriptional activating domain, then the second fusion protein comprises a DNA binding domain. The interaction of the first and second fusion proteins reconstitutes a sequence-specific transcription activating factor. The cell also comprises a reporter gene comprising a DNA sequence to which the DNA binding domain specifically binds. Expression of the reporter gene is measured. A test compound which decreases the expression of the reporter gene is a potential inducer of mitosis or cell cycle progression.
The present invention thus provides the art with reagents and methods of regulating mitosis or cell cycle progression of human cells and of treating disorders associated with alterations in cell cycle progression.